My Rheumatologist explained Fibromyalgia as being CAUSED by chronic pain, (meaning there is an underlying injury or disease) this chronic pain changed the brain until our entire body is in pain. (back to the Substance P) He goes on to say that by treating the CAUSE of my pain, Psoriatic Arthritis is the primary disease of mine, he is aleviating the Fibromyalgia. Makes sense to me, when the arthritis is calm, so is the Fibro!